This invention relates to a material sensing switch and more particularly to an improved material sensing switch which is ideally suited for use in dusty conditions such as bins, tanks, cement silos, etc.
Many material sensing switches have been previously provided but none have met with considerable success due to the environment in which they are normally used to sense the presence or absence of material. Material sensing switches are commonly used in bins or the like to sense the presence or absence of material at a particular level within the bin. It is essential that a switch be provided which will function in dusty conditions and which will not create dangerous and hazardous sparks. It is also essential that the switches be comprised of a material which will not be damaged by the corrosive nature of the materials being sensed.
In assignee's earlier patents, namely U.S. Pat. Nos. 4,031,342 and 4,044,209, improved material sensing switches are described. This invention is designed to completely eliminate any possibility of sparks or arcs being created by the switching device.
Therefore, it is a principal object of the invention to provide an improved material sensing switch.
A further object of the invention is to provide an improved material sensing switch which utilizes a fiber optic switch mechanism thereby eliminating the possibility of dangerous sparks or arcs when the switch mechanism is actuated.
These and other objects will be apparent to those skilled in the art.